1. Field of the Invention
One embodiment of the present invention relates to a power storage device and an electronic device.
Note that one embodiment of the present invention is not limited to the above technical field. One embodiment of the invention disclosed in this specification and the like relates to an object, a method, and a manufacturing method. One embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Specifically, examples of the technical field of one embodiment of the present invention disclosed in this specification include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, a method for driving any of them, and a method for manufacturing any of them.
Note that electronic devices in this specification generally mean devices driven by electricity; and electro-optical devices, information terminal devices, and the like are all electronic devices. Some electronic devices incorporate a power storage device. Note that “incorporate” in this specification refers not only to incorporation of a power storage device in a manner that the device cannot be detached for replacement, but also to incorporation of a power storage device in a manner that the device as a form of battery pack or the like can be freely detached.
2. Description of the Related Art
In recent years, a variety of power storage devices such as lithium-ion secondary batteries, lithium-ion capacitors, and air batteries have been actively developed. In particular, demand for lithium-ion secondary batteries with high output and high energy density has rapidly grown with the development of the semiconductor industry, for the uses of electronic equipment, for example, portable information terminals such as mobile phones, smartphones, and laptop computers, portable music players, and digital cameras; medical equipment; and next-generation clean energy vehicles such as hybrid electric vehicles (HEVs), electric vehicles (EVs), and plug-in hybrid electric vehicles (PHEVs). The lithium-ion secondary batteries are essential for today's information society as rechargeable energy supply sources.
The development of wearable devices that are used while being worn by the users is also actively carried out. In order to be used more comfortably by the users, wearable devices often have curved shapes or have flexibility. In addition, power storage devices with flexibility and bendability to be incorporated in such wearable devices are being developed.
For example, Patent Document 1 discloses a sheet-like power storage device which can be bent in at least one axis direction, and electronic devices incorporating the power storage device. Patent Document 2 discloses a flexible secondary battery and an arm-worn electronic device including the secondary battery.